Thermo Fisher Scientific IL-21 Recombinant Rabbit Monoclonal Antibody (012)

Applications

• ELISA (ELISA): 1:5,000–1:10,000 dilution tested

Product Specifications

Product Specific Information

This product is preservative-free. It is recommended to add sodium azide to avoid contamination (final concentration 0.05%–0.1%).

Recombinant rabbit monoclonal antibodies are produced using in vitro expression systems. The antibody DNA sequences from immunoreactive rabbits are cloned and screened for optimal production.
Advantages include:

• Enhanced specificity and sensitivity
• Lot-to-lot consistency
• Animal origin-free formulation
• Broader immunoreactivity due to the rabbit immune repertoire

This antibody is specific for Mouse IL-21.

Target Information

IL-21 is a 17 kDa immunomodulatory cytokine mainly produced by Natural Killer (NKT) cells, T helper 17 (Th17), and T follicular helper (TFH) cells.
In TFH cells, IL-21 expression induces autocrine signaling via IL-21R and STAT3, leading to transcriptional activation by Bcl6. Similar to IFN-γ in Th1 and IL-4 in Th2 cells, IL-21 is critical for TFH cell development and effector function.

IL-21 promotes:

• T cell-dependent B cell differentiation into plasma and memory cells
• IgG production stimulation
• Apoptotic signaling induction in naive B cells

In Th17 cells, IL-21 and autocrine feedback through STAT3, IRF4, and RORγt upregulate IL-23R, supporting Th17 maturation and maintenance by IL-23.
While upregulating IRF4 and RORγt, IL-21 downregulates Foxp3.
IL-21 deficient mice show protection from chemically induced colitis due to reduced Th17-associated molecule expression, whereas elevated IL-21 levels are observed in colitis models.

For Research Use Only. Not for use in diagnostic procedures. Not for resale without express authorization.